A Chinese company whose parts appear in the iPhone 3GS is supposedly selling midboards for a next-generation iPhone, and claims to have pictures of the entire 4G unit.

China OnTrade lists the "Apple iPhone 4 Generation Midboard" for $23.42, in stock and shipping within 12 business days. The midboard itself is unremarkable: It's got holes for a mainboard and camera, a space for the usual charger, plus screw-threads and bezel brackets, but none of this says anything about the phone itself.

The real interesting stuff is apparently still to come. "We also have final pictures of iPhone 4 Generation with amazingly beautiful back cover that will come here up soon. Please check for updates," China OnTrade says on its Web site.

China OnTrade has proven reliable before. In May, the company sold parts that it claimed were spares from a next-generation iPhone. As Gizmodo notes, those parts showed up in teardowns of the iPhone 3GS when it was released in June.

There is another wrinkle to the story: In late-October, China OnTrade began selling an "Apple iTablet iPhone 4 Generation SIM Tray." The use of "iTablet" and "iPhone" makes me wonder if something's lost in translation and we're just talking about the rumored tablet, or that the same SIM tray will appear in both devices. If the iPhone is still on track for summer updates with the tablet coming sooner, it would make more sense for China OnTrade to get tablet parts now. On the other hand, the midplate measures 4.5-by-2.3 inches, which lines up nicely with existing iPhones.

It's worth noting that Apple gave Gizmodo a headache for reporting that Worldwide Marketing Vice President Phil Schiller said "no more Apple products this year," when he actually said that "the holiday lineup is set." So we could see a new something-or-other pretty soon. At the very least, China OnTrade's claims can't be dismissed as categorically false.